Time domain astronomy with the next-generation Gemini-North adaptive optics facility

The International Gemini Observatory/NSF NOIRLab is currently developing GNAO, the next-generation adaptive optics (AO) facility for the 8-m Gemini-North telescope. GNAO's primary science instrument will be the future Gemini Infrared Multi-Object Spectrograph (GIRMOS) which will use the AO-compensated beam from GNAO to offer (i) wide-field near-infrared imaging with near diffraction-limited performance over fields of approximately 20 arcsec× 20 arcsec, (ii) seeing-enhanced imaging over fields of up to 85 arcsec×85 arcsec, and (iii) spatially-resolved near-infrared spectroscopy through up to four deployable integral field units. Time domain applications have played a major role in defining GNAO's capabilities. As a queue-operated, 4-laser-guide-star adaptive optics system, GNAO will be a premier facility for following up gamma-ray bursts and transient multimessenger events at high angular resolution. This paper describes the operational requirements and concepts facilitating rapid-response observations with GNAO. We also present a preview of the anticipated sensitivity and astrometric performance when using GNAO together with the GIRMOS imaging mode.